msem-instigator

As an additional cost to cast this spell, tap an untapped artifact you control.
Target player discards two cards.

Whenever a creature you control dies, Insidious Terror gets +1/+0 and gains menace until end of turn.

Whenever a creature you control dies, you may put a +1/+1 counter on target creature you control.

Each player exiles up to X cards from their graveyard. Then each player loses life, discards cards and sacrifice creatures equal to X minus the number of cards that player exiled this way.

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Flying
When Heartstabber Mosquito enters, if it was kicked, destroy target creature.

Put target creature card from a graveyard onto the battlefield under your control. If that card was put into that graveyard this turn, it enters with an additional +1/+1 counter on it.

Flying (This creature can't be blocked except by creatures with flying or reach.)
At the beginning of your upkeep, put a +1/+1 counter on Fleshrender Demon and you lose 1 life.

{3}{B}: Regenerate Flesh Hoarder Ghoul. (The next time this creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)

Enchant creature
Enchanted creature has flying and “Sacrifice a creature: This creature gets +2/+1 until end of turn.”
When Fallen Ideal is put into a graveyard from the battlefield, return Fallen Ideal to its owner's hand.

Target creature gets +2/+0 and gains lifelink until end of turn.

Whenever Consuming Doom or another enchantment you control enters, you may have target creature get -1/-1 until end of turn.
Whenever a source an opponent controls destroys an enchantment you control, that player sacrifices a creature.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets -2/-2.
Whenever enchanted creature blocks, its controller loses 2 life.

Destroy target creature. You gain 1 life for each card in its controller's graveyard.

Target player sacrifices a creature. If you control an artifact, draw a card.

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Blood-Tithe Harpy enters, target player loses 1 life and you gain 1 life.

Enchant creature
Enchanted creature gets +2/+2 and has lifelink.

Kicker {1}{B} (You may pay an additional {1}{B} as you cast this spell.)
All creatures get -1/-1 until end of turn. If this spell was kicked, creatures your opponents control get an additional -1/-1 until end of turn.

Ammbradu Parasite gets +1/+1 as long as you control a Forest.
{4}{G}: Target creature must be blocked this turn if able.

Remove all counters from all permanents and exile all tokens.

Draw three cards, then discard a card.

Flash (You may cast this spell any time you could cast an instant.)
When Volatimancer enters, you may have target creature have base power and toughness 1/1 until end of turn.

When Vedalken Wingcrafter enters, create a 1/1 colorless Thopter artifact creature token with flying.

When Vedalken Machinist enters, create a 1/1 colorless Thopter artifact creature token with flying.
At the beginning of your upkeep, if you control three or more artifacts, draw a card.

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Tap up to three target creatures. If this spell was kicked, those creatures don't untap during their controller's next untap step.

Exile up to X target instant and/or sorcery cards with total mana value X or less from your graveyard. You may cast a copy of each card exiled this way without paying its mana cost. Exile Total Recall.